<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <!-- 先禁用元素 -->
  <button id="djs" disabled>阅读(60)才可以</button>
  <script>
    const btn = document.querySelector('#djs')
    let i = 3

    let n = setInterval(function () {
      i--

      btn.innerHTML = `我已经阅读(${i})`
      if (i === 0) {
        clearInterval(n)
        // 定时器停止则开启
        btn.disabled = false
        btn.innerHTML = "同意"
      }
      // console.log(i--);
    }, 1000)

    // console.log(btn.innerHTML);
  </script>
</body>

</html>